Stoker



Jan. 5, 1937. w. L. GOTWALS, JR 2,057,152

STOKER Filed March 17, 1936 I 2 Sheets-Sheet 1 BWWE- Jan. 5, 1937. w. L. GOTWALSJJR 2,067,152

' r I STOKER Filed March 17, 1956 2 Sheets-Sheet 2 lNl/f/VTO/Q' MLL/HM L. GOTWHLS, JR.

Po m s, 1937 STATES STOKEB William L. Gotwals, Jr., Norrlstown, Pa., assignor to John Wood Manufacturing Company, Inc., Conshohocken, Pa., a corporation of Delaware Application March 17, 1936, Serial No. 69,260

4 Claims. (Cl. 110- 45) My invention relates to stokers of the general class disclosed in Letters Patent of the United States 1,992,149 granted February 19, 1935, to Charles G. O'Hara, etc. for an Automatic stoker.

5 Such stokers include a foraminous grate or burner bowl, means for forcibly progressing solid fuel and air to said bowl, to effect combustion of fuel in the bowl, and means for forcibly progressing ashes away from said bowl. Such means for progressing the fuel and ashes are respective fuel and ashes, to progress them in only one direction of reciprocation of said bars. The fuel conveyer is. operative to force the fuel upwardly through the bottom of the grate bowl, and the ashes, product of combustion thereof, are thus pushed over the circumferential fiat rim of said bowl. In said patent,-means were provided for automatically knocking the under side of said rim for the purpose of jarring the ashes from said rim. The object and effect of my invention is to eliminate the knocking device aforesaid and substitute therefor a cylindriform ring which surrounds said rim, and is supported upon pivots at opposite sides of a diameter of said rim and connected with one of said conveyer bars so as to be oscillated by the reciprocation of that bar,

with the efiect of automatically shearing and sweeping from the perimeter of said rim ashes, whether of the clinkering type or not. My improvement is highly advantageous in that it permits the combustion of cheap coals of the clinkering type not hitherto susceptible of use in automatic stokers of said class.

My invention includes the various novel fea tures of construction and arrangement hereinafter more definitely specified.

In said drawings, Fig. I is a perspective view of an automatic stoker embodying my invention, parts of the casing being omitted for clarity of illustration. Fig. II is a plan view of a portion of the end of the structure shown in Fig. I including the grate bowl and its appurtenances. Fig. III is a fragmentary side elevation of the grate end of the structure shown in Figs. I and II. Fig. IV is a diametrical sectional view of said structure taken on the line IV, IV in Figs. II and III, in the direction of the arrows on said line, with the double link for tilting the ring turned down from its normal position to show its configuration. Fig. V is a fragmentary elevation of the gearing connecting the electric motor with the means for reciprocating the coal and ash conveyers; said gearing being indicated 7 at the right hand side of the coal hopper in Fig. 1.

Fig. VI is a fragmentary vertical sectional view showing the relations between the outlet of the coal hopper and that of the ash conveyer indicated in Fig. I. Fig. VH is a fragmentary plan view of the ash conveyer indicated in Figs. '1 ili 'id HI showing the wedge shape of its features The foraminous grate or burner bowl I which has, throughoiit its conical portion, perforations such as indicated at 2 in Fig. IV to admit air to the fuel to be burned therein, is rigidly supported on the fuel conduit, which includes the elbow 3 and the cylindrical tube 4, the outer end of which is fixed in the hopper housing 5. Said housing 5, which is conveniently formed of cast metal, is adapted to normally rigidly support the fuel hopper 6, which is conveniently formed of sheet metal.

Said burner bowl i and the fuel conduit above described are partly encased and supported by an air conduit including the air bowl III which has the annular shoulder ll upon which the flange I2 of said burner bowl i rests. Said air bowl is supported by the discharge mouth l3 of the air conduit.

Coal is forcibly delivered from said hopper housing 5, through said fuel conduit 3 and 4, upwardly within said burner bowl I, by means of the conveyer comprising the reciprocatory bar It which is operatively connected with the electric motor l5, indicated in Fig. I, which also operates the rotary blower within the casing is indicated in said figure.

Said motor is also operatively connected with the ash conveyer including the reciprocatory bar l'l which is supported at the bottom of the ash conduit l8 which is trough-shaped and rigidly connected with said coal and air conduits as indicated in Fig. I. Said conduit [8 includes opposite side plates which are upwardly and outwardly flared to house the ash dofi er blades I 8' which are carried by, and extend upwardly from,

said bar H, and facilitate the gravitation of the ashes down said plates. Said plates, which are the same height as said blades, are omitted to show the other features of construction.

The ash ring I9 is conveniently composed of four quarter sectors, and forms a flat circular rim extending in a substantially horizontal plane from the edge of said burner bowl I and said ring and bowl are in coaxial relation with the oscillatory ring 20 which is spaced vertically and horizontally therefrom. Said ring 20 has at diametrically opposite sides thereof respective pendent arms 2| having axially alined pivotal supports 22 at a diameter of the air bowl and said ring is held in coaxial relation with said bowls by the spacing sleeves 23 ,on said supports 22. As

shown in Fig. IV,.,said pivotal supports 22 arec'ylindrical trunnions which are conveniently rig- --idly mounted in bearings H) in said air bowl l and have cylindrical rollers 22 interposed between said pivots 22 and said arms 2! to facilitate the rocking movement of the latter. Said rollers 22' are prevented from axial displacement on said trunnions by shoulders on the trunnions and the spring collars 2| which are snapped into grooves in the'trunnions. The'latter are conveniently removably' secured in said bearings ll) by the bolts 3| provided with the nuts 32, as shown in Fig. IV. v

Although said ring 20 might be formed of a single strip of wrought metal, I find it convenient to form it of two. similarly shaped substantially semi-circular pieces, the-opposed ends of which are rigidly connected by bridge members 36 which, as indicated in Fig. II, are preferably riveted at one end to one ring section and connected with the other ring section by bolts 35 and nuts 36. Such construction and arrangement facilitate and minimize the cost of repairs to said ring 20, which is preferably made of self-hardening steel alloy capable of retaining its hardness under the high temperatures to which it is subjected.

The U-shaped double link 24 has its opposite ends respectively pivotally connected at 25 with the lower ends of the respective ring arms 2|, and the bight 26 of 'said' double link 24 is 'journaled in the bearing 21 which is rigidly connected with the end of said ash conveyer ll. Said conveyer is supported at that end by the rod 29 which is mounted to reciprocate in the tubular bearing 30 which is cast as part of said air conshaped portions H which are inclined oppositely to the wedge-shaped portions I4 of the coal conveyer bar, with the effect of slipping idly through the ashes when said conveyer bar H moves to the left in Fig. III but engaging said ashes to forcibly convey them to the right in Fig. HI when the bar is moved in that direction. They are discharged through the housing 5, and behind the hopper 6, through the outlet 31 in the right hand side of said housing shown in Fig. VI, from which they may be picked up by an endless belt conveyer, which is not shown.

The armature shaft 38, of said electric motor l5, which is in coaxial relation with the circular portion of the blower casing l6, shown in Fig. I, and which carries the blower rotor, is connected, by suitable gearing in the motor casing IS, with the counter shaft 39 which extends transversely thereto and carries the gear pinion 40, shown in Fig. V, in mesh with the gear 4| which is journaled on the stud shaft 42 project- 'ing from the housing 5. Said gear 4| carries the with the yoke 50. The end of the coal conveyer bar M is slip fitted through a bearing in said yoke 50 and provided withthe nut 5| at its end so that there is lost motion between said yoke and bar It, limited by the adjustment of said nut and the sleeve 52 which is interposed between said nut and the bearing onsaid yokethrough which said bar it slips. Said ash conveyer bar I7 is rigidly connected with said yoke, conveniently by bolts 53. The arrangement described is such that the reciprocatory movement of said ash conveyer bar I! is invariable and determined by the throw of the crank pin 43; whereas the reciprocation of the coal conveyer bar It is variable as above described to vary the rate of supply of coal to the grate bowl I.

Continuous reciprocation of the ash conveyer bar I1, driven by said electric motor l5, of course reciprocates the double link 24 and-consequently, continuously oscillates the ring by its arms 2 I, with the efiect of shearing andsweeping from the perimeter of said ash ring l9 all clinker and ashes which have been pushed to said perimeter by the forcible upward progression of the coal into said burner bowl I by the action of said coal conveyer l4.

However, I do not desire to limit myself to the precise details of construction and arrangement herein set forth, as it is obvious that various grate, having its axis substantially vertical and a substantially horizontal rim; of a conveyer adapted to force fuel upwardly within said grate; a conveyer for forcing ashes away from said grate; means adapted to forcibly discharge clinker and ashes from said grate vrim, including a ring arranged coaxially with the rim and spaced outward and upward therefrom; means affording axially alined horizontal pivotal supports for said ring at diametrically opposite sides thereof; arms extending downwardly from said ring, and diametrically opposed thereon, and engaged by 'said pivotal supports; and means operatively connecting one of said conveyers with said ring arm, for

oscillating said ring on said supports, to extend above and below the rim, transversely to the plane of said graterim, and dislodging clinker and ashes from said rim into cooperative relation with said ash conveyer.

2. A structure as in claim 1, wherein the us cillatory ring has means for connecting it with said conveyer which actuates it, said means comprising a U-shaped double link having its bifurcations respectively pivotally connected with the lower ends of said arms.

3. A structure as in claim 1, wherein the grate is a bowl open at the bottom in communication with a tubular fuel conduit extending horizontally thereto and said grate bowl is supported by an air bowl open at the bottom and in communication with an air conduit surrounding said fuel conduit; and said pivotal supports are trunnions detachably rigidly secured in hearings in said air bowl.

4. A structure as in claim 1, wherein the oscillatory ring is formed of oppositely counterpart substantially semi-circular sections and said sections are connected by bridge members overlapping their opposed ends.

WILLIAM L. GOTWALS. JR.

DISCLAIMER 2,067,152.Willia1n L. Gotwdls, Jri, Norristown, Pa. STOKER. Patent dated January 5, 1937. Disclaimer filed May 18, 1938, by the assignee, John Wood lllaml facturing Company, Inc.

Hereby enters this disclaimer to claims 1, 2, 3, and 4 in said Letters Patent.

[Ojficial Gazette, June 14, 1938.] 

